集成PMOS管变容特性分析与仿真建模

Analysis and Simulation Modeling for Variable Capacitance Characteristic of Integrated PMOS Transistor

为适应PMOS变容管在集成电路设计中的晶体管级仿真,在分析MOS变容管特性的基础上,通过确定关键点、以曲线拟合的方法建立与工艺参数相关的PMOS集成变容管高频特性模型。选用Charted 0.35μm这个特定的工艺库,并离散地改变电容连接的PMOS静态偏压、用HSpice仿真并对寄生电容提取后描绘出变容特性的准静态曲线;用Matlab对所建的简化高频变容模型进行仿真、得出高频变容曲线。仿真与理论结果相比较表明:PMOS管变容特性曲线与理论曲线的变化趋势吻合;2种仿真对变容显著区吻合较好。从而证明了PMOS集成变容管高频简化模型的正确性。

In order to adapt transistor-level simulation for PMOS variable capacitance transistor in the integrated circuit design,based on the analysis of the MOS variable capacitance characteristic,a high-frequency characteristic model related to process parameters of the integrated PMOS transistor was established with the methods of curve fitting and determinaton of key points.During modeling,the Charted 0.35μm process database was selected,the static bias of capacitor-connected PMOS was changed dispersively,and the quasi-static characteristics curve was described after extracting the parasitic capacitance by HSPICE simulation.A simplified high-frequency variable capacitance model was simulated with Matlab,thereby the curve of high-frequency variable capacitance curve was derived.The results show that the high-frequency characteristic curve trend of PMOS variable capacitance transistor is consistent with the theoretical curves.Furthermore,two kinds of simulation agrees with each other in the variable capacitance significant region.Thus,it is proved that the simplified high-frequency model of integrated PMOS variable capacitance is correct.